发明名称 |
Optical disc having protective cover |
摘要 |
An optical disc assembly has an optical disc and a protective cover. The optical disc has a surface adapted to have optically recorded thereon data consisting of a series of laser ablated pits recorded as a series of concentric data tracks. The pits have small size and high surface density. The protective cover has a permanent optical recording at one surface thereof consisting of a series of visible marks. The marks are an order of magnitude larger than the pits and have a much lower surface density. Memory data is recorded on the optical disc and positional data, comprising a map of the memory data surface, is recorded on the cover. This allows the use of separate positional data and memory data monitoring channels which facilitates the recording of a blank optical disc and subsequent memory data access.
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申请公布号 |
US4672600(A) |
申请公布日期 |
1987.06.09 |
申请号 |
US19860835927 |
申请日期 |
1986.03.04 |
申请人 |
NORTHERN TELECOM LIMITED |
发明人 |
BALSTON, NEIL K.;ANDERSON, KEITH D.;WILLEMSEN, HERMAN W. |
分类号 |
G06K7/10;G11B7/24;G11B23/30;G11B27/19;(IPC1-7):G11B23/00;G11B7/00 |
主分类号 |
G06K7/10 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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